Ancient Cuzco citizen (4)
I believe the answer is:
inca
'ancient cuzco citizen' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for inca that I've seen before include "Old Peruvian people" , "Ancient civilisation of Peru" , "Ancient South American" , "mountain dweller" , "Pyramid builders" .)